The U.S. Internal Revenue Service (IRS) today sharply revised previous estimates on the number of citizens that were hit by tax refund fraud since 2014 thanks to a security weakness in the IRS’s own Web site. According to the IRS, at least 724,000 citizens were victims of refund fraud after crooks figured out how to abuse a (now defunct) IRS Web site feature called “Get Transcript” to steal victim’s prior tax da